Email can’t be delivered

I'm a Singaporean.

I replied 2 emails which received from 2 Japanese but all the emails that sent bounced. The given email address is xxxx ato yahoo.co.jp
As @ and underscore were not clearly written, i sent xxxx_ato@yahoo.co.jp and xxxxato@yahoo.co.jp, but both bounced back. Beside the email address could be no longer in use, is there any other reason whu it can't be delivered？

I also received another email from Japan whereby he use the star symbol position before yahoo and note that the star symbol = at. So i assumed at = @. I'm curious, is it because the Japanese keyboard unable to enter @ ?

Hope someone can help. Thank you.

No, the Japanese keyboard has an @ key. These people were probably just trying to obfuscate their email addresses to try to prevent spambots from finding them. Try replacing ato with @ (ato=at=@) and drop the spaces and it should work.

Hi @0@

Thank you for the response.
I've replaced ato with @ and still bounced back. Sigh..

It's ok. Thanks.

So you wrote the address as xxxx@yahoo.co.jp and it still bounced?

Ya. I even registered a yahoo.co.jp email address and still bounced. Looks like i need to give up already. Maybe the address no longer in use.
:(